Bambietta Basterbine is a Quincy and a member of the Wandenreich's Sternritter, holding the title "E — The Explode." She considers herself the leader among the female Sternritter known as the Bambies — Liltotto, Candice, Meninas, and Giselle — though this position is largely self-appointed rather than an officially recognized rank.

She took part in the Wandenreich's first invasion of the Soul Society, slaughtering numerous Shinigami before being intercepted by 7th Division Captain Sajin Komamura. During their battle, she used her medallion to steal Komamura's Bankai, though he later reclaimed it. After the Wandenreich's retreat, she was visibly unsettled when Yhwach announced Uryū Ishida as his successor.

During the second invasion, Bambietta faced both Komamura and 5th Division Captain Shinji Hirako. She activated her Quincy: Vollständig, Zofiel, and successfully wounded Shinji with her explosive abilities. However, Komamura, having used the Humanization Technique at the cost of his heart, ultimately defeated her decisively.

Badly wounded, Bambietta was left alone amid the rubble of the battlefield, terrified of what defeat might mean for a Sternritter — unaware that her comrades were about to arrive.